core

### Constructing a Circle at a Scan's Minimum Point

This feature lets you construct a 2D circle of a given radius at a minimum point along a linear scan. PC-DMIS finds the minimum point by using a starting point and a downward direction vector (as shown below). Think of the downward vector as a gravity vector. The circle will, in a sense, be "pulled" in that direction.

A - Scan
B - Start Point
C - Down Vector
D - Final Position

Minimum point of a circle along a scan with a defined downward vector and starting point.

PC-DMIS projects the scan to the current workplane and the circle will lie in a plane parallel to the workplane. The scan will be interpreted as a line between consecutive points (piecewise linear). Thus, the circle that is placed at the minimum point along the scan will not "fall" between two consecutive scan points, but instead will be constrained to touch a line connecting the two points.

Valid Input Types

The input for this construction must be a line type scan. This excludes all scans designed to scan a surface: Patch, UV, Grid, Multisection, Manual Laser, and Cylinder.

Construction Procedure

To start this construction:

1. Access the Construct Circle dialog box (Insert | Feature | Constructed | Circle).

2. Select the Scan Minimum option.

3. Select a linear scan from the feature list. You cannot use a surface scan.

4. Click the Search Setup button.

5. The Circle Minimum Search Setup dialog box appears:

Circle Minimum Search Setup dialog box

6. Define the circle’s start point, its down direction, and its diameter.

7. Click OK to construct the circle. PC-DMIS constructs the circle and inserts the construction command into the Edit window:

Cutaway view showing a circle (CIR15) constructed at the minimum point on the scan line (SCN1)

More:

Rules for Construction

No Local Minimum

Edit Window Command for a Constructed Scan Minimum Circle

Additional Examples